Objective To evaluate type B2 vessels for predicting the invasion depth of superficial esophageal squamous cell carcinoma (SESCC) under narrow band imaging‑magnifying endoscopy (NBI‑ME), and to analyse the influencing factors of over‑prediction and under‑prediction. Methods A total of 86 SESCC patients with 86 lesions confirmed by postoperative pathology, who underwent NBI‑ME to evaluate the invasion depth of esophageal tumor and were observed for type B2 vessels in Department of Digestive Endoscopy of Fujian Provincial Hospital from January 2015 to April 2020, were included in the case‑control study. According to the postoperative pathological results, the patients were divided into the correct prediction group (n=25) and the wrong prediction group (n=61), and the accuracy of prediction was calculated. The wrong prediction group was further divided into the over‑prediction group (n=49) and the under‑prediction group (n=12) to find the influencing factors of over‑prediction and under‑prediction, respectively. Further, multivariate Logistic analysis was performed to explore the independent influential factors for the prediction. Results The accuracy of type B2 vessels under NBI‑ME for predicting the invasion depth of SESCC was only 29.07% (25/86), and the over‑prediction rate and under‑prediction rates were 56.98% (49/86) and 13.95% (12/86), respectively. Univariate analysis showed that the classification of type B2 area (χ2=36.25, P<0.001), the distinct endoscopic features (nodules, thickening and obvious depression, χ2=22.90, P<0.001), and inflammation around type B2 vessels (χ2=9.54, P=0.004) were related to the over‑prediction of the invasion depth of SESCC, and the distinct endoscopic features were related to the under‑prediction of the invasion depth (P=0.016). Multivariate Logistic regression analysis showed that B2-narrow (type B2 area ≤5 mm) (P<0.001, OR=241.988,95%CI:15.229-3 845.252) and inflammation around type B2 vessels (P=0.033, OR=12.801, 95%CI: 1.226-133.713) were independent risk factors for over‑predicting the invasion depth of SESCC, while the distinct endoscopic features were independent protective factors for over‑prediction (P<0.001, OR=0.012, 95%CI: 0.001-0.150). The distinct endoscopic feature was an independent risk factor for under‑predicting invasion depth of SESCC with type B2 vessels (P=0.027, OR=7.899, 95%CI: 1.259-49.565). Conclusion The accuracy of predicting the invasion depth of SESCC is low only based on type B2 vessels in NBI‑ME, and over‑prediction is prone to occur. B2-narrow, inflammation around type B2 vessels and without nodules, thickening and obvious depression are closely related to the over‑prediction of invasion depth of SESCC by type B2 in NBI‑ME, and nodules, thickening and obvious depression are closely associated with the under‑prediction. However, whether the combined assessment of type B2 vessels under NBI‑ME and endoscopic manifestation can improve the accuracy of prediction needs to be confirmed by further studies.